Surgical needles are well known in the medical arts. The needles typically have a curved, elongated body with a distal piercing point and a proximal suture mounting end. Sutures may be mounted either into holes drilled into the proximal ends of the needle or channels stamped into the proximal ends of the needles. Sutures are mounted to the drilled holes or channels through a conventional swaging process wherein the proximal end of a needle is stamped or hit with a die thereby compressing the suture within the hole or channel.
Although there are a variety of surgical needles known in this art, two types of conventional surgical needles are widely and typically used. These needles include taper point needles and cutting edge needles. Taper point needles taper to a distal piercing point and have a smooth outer surface. Cutting edge needles also taper to a piercing point and have one or more cutting edges with an otherwise smooth outer surface. As mentioned previously, taper point needles and cutting edge needles and methods of manufacturing these needles are known in the art and are disclosed for example in commonly owned U.S. Pat. No. 5,477,604 and commonly owned copending U.S. patent application Ser. No. 08/633,607, which are incorporated in their entirety by reference. Taper point surgical needles typically have a taper from a middle section of the needle body which ends in a distal piercing point. The taper is often expressed as a ratio of the length of the taper section to the diameter of the wire used to form the needle, e.g., 12D/1D or 12:1. It is known that the higher the taper ratio is, the more slender the taper, and the resistance to penetration through tissue will typically be lessened. However, the more slender the taper, the less will be the mechanical strength for needles manufactured from the same material. The converse is also to be expected for needles having lower taper ratios. Taper point needles having taper ratios of 8:1 or smaller were, in the past, the industry standard. Today, most taper point needles have a 12:1 taper ratio.
There is a constant need in this art for improved surgical needles having good penetration characteristics (i.e., resistance to penetration through tissue) and good mechanical characteristics such as bending strength, etc. There is also a constant need in this art for taper point needles which have configurations that are readily manufactured in an automated manufacturing process.